mirror of
https://github.com/xenia-project/FFmpeg.git
synced 2024-11-24 20:19:55 +00:00
309 lines
9.7 KiB
C
309 lines
9.7 KiB
C
/*
|
|
* Micrsoft RLE Video Decoder
|
|
* Copyright (C) 2003 the ffmpeg project
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file msrle.c
|
|
* MS RLE Video Decoder by Mike Melanson (melanson@pcisys.net)
|
|
* For more information about the MS RLE format, visit:
|
|
* http://www.pcisys.net/~melanson/codecs/
|
|
*
|
|
* The MS RLE decoder outputs PAL8 colorspace data.
|
|
*
|
|
* Note that this decoder expects the palette colors from the end of the
|
|
* BITMAPINFO header passed through palctrl.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include "avcodec.h"
|
|
#include "dsputil.h"
|
|
|
|
typedef struct MsrleContext {
|
|
AVCodecContext *avctx;
|
|
AVFrame frame;
|
|
|
|
const unsigned char *buf;
|
|
int size;
|
|
|
|
} MsrleContext;
|
|
|
|
#define FETCH_NEXT_STREAM_BYTE() \
|
|
if (stream_ptr >= s->size) \
|
|
{ \
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: stream ptr just went out of bounds (1)\n"); \
|
|
return; \
|
|
} \
|
|
stream_byte = s->buf[stream_ptr++];
|
|
|
|
static void msrle_decode_pal4(MsrleContext *s)
|
|
{
|
|
int stream_ptr = 0;
|
|
unsigned char rle_code;
|
|
unsigned char extra_byte, odd_pixel;
|
|
unsigned char stream_byte;
|
|
int pixel_ptr = 0;
|
|
int row_dec = s->frame.linesize[0];
|
|
int row_ptr = (s->avctx->height - 1) * row_dec;
|
|
int frame_size = row_dec * s->avctx->height;
|
|
int i;
|
|
|
|
/* make the palette available */
|
|
memcpy(s->frame.data[1], s->avctx->palctrl->palette, AVPALETTE_SIZE);
|
|
if (s->avctx->palctrl->palette_changed) {
|
|
s->frame.palette_has_changed = 1;
|
|
s->avctx->palctrl->palette_changed = 0;
|
|
}
|
|
|
|
while (row_ptr >= 0) {
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
rle_code = stream_byte;
|
|
if (rle_code == 0) {
|
|
/* fetch the next byte to see how to handle escape code */
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
if (stream_byte == 0) {
|
|
/* line is done, goto the next one */
|
|
row_ptr -= row_dec;
|
|
pixel_ptr = 0;
|
|
} else if (stream_byte == 1) {
|
|
/* decode is done */
|
|
return;
|
|
} else if (stream_byte == 2) {
|
|
/* reposition frame decode coordinates */
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
pixel_ptr += stream_byte;
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
row_ptr -= stream_byte * row_dec;
|
|
} else {
|
|
// copy pixels from encoded stream
|
|
odd_pixel = stream_byte & 1;
|
|
rle_code = (stream_byte + 1) / 2;
|
|
extra_byte = rle_code & 0x01;
|
|
if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
|
|
(row_ptr < 0)) {
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < rle_code; i++) {
|
|
if (pixel_ptr >= s->avctx->width)
|
|
break;
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
|
|
pixel_ptr++;
|
|
if (i + 1 == rle_code && odd_pixel)
|
|
break;
|
|
if (pixel_ptr >= s->avctx->width)
|
|
break;
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
|
|
pixel_ptr++;
|
|
}
|
|
|
|
// if the RLE code is odd, skip a byte in the stream
|
|
if (extra_byte)
|
|
stream_ptr++;
|
|
}
|
|
} else {
|
|
// decode a run of data
|
|
if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
|
|
(row_ptr < 0)) {
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
|
|
return;
|
|
}
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
for (i = 0; i < rle_code; i++) {
|
|
if (pixel_ptr >= s->avctx->width)
|
|
break;
|
|
if ((i & 1) == 0)
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte >> 4;
|
|
else
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte & 0x0F;
|
|
pixel_ptr++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* one last sanity check on the way out */
|
|
if (stream_ptr < s->size)
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: ended frame decode with bytes left over (%d < %d)\n",
|
|
stream_ptr, s->size);
|
|
}
|
|
|
|
|
|
|
|
static void msrle_decode_pal8(MsrleContext *s)
|
|
{
|
|
int stream_ptr = 0;
|
|
unsigned char rle_code;
|
|
unsigned char extra_byte;
|
|
unsigned char stream_byte;
|
|
int pixel_ptr = 0;
|
|
int row_dec = s->frame.linesize[0];
|
|
int row_ptr = (s->avctx->height - 1) * row_dec;
|
|
int frame_size = row_dec * s->avctx->height;
|
|
|
|
/* make the palette available */
|
|
memcpy(s->frame.data[1], s->avctx->palctrl->palette, AVPALETTE_SIZE);
|
|
if (s->avctx->palctrl->palette_changed) {
|
|
s->frame.palette_has_changed = 1;
|
|
s->avctx->palctrl->palette_changed = 0;
|
|
}
|
|
|
|
while (row_ptr >= 0) {
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
rle_code = stream_byte;
|
|
if (rle_code == 0) {
|
|
/* fetch the next byte to see how to handle escape code */
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
if (stream_byte == 0) {
|
|
/* line is done, goto the next one */
|
|
row_ptr -= row_dec;
|
|
pixel_ptr = 0;
|
|
} else if (stream_byte == 1) {
|
|
/* decode is done */
|
|
return;
|
|
} else if (stream_byte == 2) {
|
|
/* reposition frame decode coordinates */
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
pixel_ptr += stream_byte;
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
row_ptr -= stream_byte * row_dec;
|
|
} else {
|
|
/* copy pixels from encoded stream */
|
|
if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
|
|
(row_ptr < 0)) {
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (1)\n");
|
|
return;
|
|
}
|
|
|
|
rle_code = stream_byte;
|
|
extra_byte = stream_byte & 0x01;
|
|
if (stream_ptr + rle_code + extra_byte > s->size) {
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: stream ptr just went out of bounds (2)\n");
|
|
return;
|
|
}
|
|
|
|
while (rle_code--) {
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte;
|
|
pixel_ptr++;
|
|
}
|
|
|
|
/* if the RLE code is odd, skip a byte in the stream */
|
|
if (extra_byte)
|
|
stream_ptr++;
|
|
}
|
|
} else {
|
|
/* decode a run of data */
|
|
if ((row_ptr + pixel_ptr + stream_byte > frame_size) ||
|
|
(row_ptr < 0)) {
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: frame ptr just went out of bounds (2)\n");
|
|
return;
|
|
}
|
|
|
|
FETCH_NEXT_STREAM_BYTE();
|
|
|
|
while(rle_code--) {
|
|
s->frame.data[0][row_ptr + pixel_ptr] = stream_byte;
|
|
pixel_ptr++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* one last sanity check on the way out */
|
|
if (stream_ptr < s->size)
|
|
av_log(s->avctx, AV_LOG_ERROR, " MS RLE: ended frame decode with bytes left over (%d < %d)\n",
|
|
stream_ptr, s->size);
|
|
}
|
|
|
|
static av_cold int msrle_decode_init(AVCodecContext *avctx)
|
|
{
|
|
MsrleContext *s = avctx->priv_data;
|
|
|
|
s->avctx = avctx;
|
|
|
|
avctx->pix_fmt = PIX_FMT_PAL8;
|
|
s->frame.data[0] = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int msrle_decode_frame(AVCodecContext *avctx,
|
|
void *data, int *data_size,
|
|
const uint8_t *buf, int buf_size)
|
|
{
|
|
MsrleContext *s = avctx->priv_data;
|
|
|
|
s->buf = buf;
|
|
s->size = buf_size;
|
|
|
|
s->frame.reference = 1;
|
|
s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
|
|
if (avctx->reget_buffer(avctx, &s->frame)) {
|
|
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
|
|
return -1;
|
|
}
|
|
|
|
switch (avctx->bits_per_sample) {
|
|
case 8:
|
|
msrle_decode_pal8(s);
|
|
break;
|
|
case 4:
|
|
msrle_decode_pal4(s);
|
|
break;
|
|
default:
|
|
av_log(avctx, AV_LOG_ERROR, "Don't know how to decode depth %u.\n",
|
|
avctx->bits_per_sample);
|
|
}
|
|
|
|
*data_size = sizeof(AVFrame);
|
|
*(AVFrame*)data = s->frame;
|
|
|
|
/* report that the buffer was completely consumed */
|
|
return buf_size;
|
|
}
|
|
|
|
static av_cold int msrle_decode_end(AVCodecContext *avctx)
|
|
{
|
|
MsrleContext *s = avctx->priv_data;
|
|
|
|
/* release the last frame */
|
|
if (s->frame.data[0])
|
|
avctx->release_buffer(avctx, &s->frame);
|
|
|
|
return 0;
|
|
}
|
|
|
|
AVCodec msrle_decoder = {
|
|
"msrle",
|
|
CODEC_TYPE_VIDEO,
|
|
CODEC_ID_MSRLE,
|
|
sizeof(MsrleContext),
|
|
msrle_decode_init,
|
|
NULL,
|
|
msrle_decode_end,
|
|
msrle_decode_frame,
|
|
CODEC_CAP_DR1,
|
|
.long_name= NULL_IF_CONFIG_SMALL("Microsoft RLE"),
|
|
};
|